Scrivener.Ecto allows you to paginate your Ecto queries with Scrivener. It gives you useful information such as the total number of pages, the current page, and the current page's entries. It works nicely with Phoenix as well.
First, you'll want to use
Scrivener in your application's Ecto Repo. This will add a paginate
function to your Repo. This paginate
function expects to be called with, at a minimum, an Ecto query. It will then paginate the query and execute it, returning a Scrivener.Page
. Defaults for page_size
can be configued when you use
Scrivener. If no page_size
is provided, Scrivener will use 10
by default.
You may also want to call paginate
with a params map along with your query. If provided with a params map, Scrivener will use the values in the keys "page"
and "page_size"
before using any configured defaults.
defmodule MyApp.Repo do
use Ecto.Repo, otp_app: :my_app
use Scrivener, page_size: 10
end
defmodule MyApp.Person do
use Ecto.Schema
schema "people" do
field :name, :string
field :age, :integer
has_many :friends, MyApp.Person
end
end
def index(conn, params) do
page =
MyApp.Person
|> where([p], p.age > 30)
|> order_by(desc: :age)
|> preload(:friends)
|> MyApp.Repo.paginate(params)
render conn, :index,
people: page.entries,
page_number: page.page_number,
page_size: page.page_size,
total_pages: page.total_pages,
total_entries: page.total_entries
end
page =
MyApp.Person
|> where([p], p.age > 30)
|> order_by(desc: :age)
|> preload(:friends)
|> MyApp.Repo.paginate(page: 2, page_size: 5)
Add scrivener_ecto
to your mix.exs
dependencies.
defp deps do
[{:scrivener_ecto, "~> 1.0"}]
end
First, you'll need to build the test database.
MIX_ENV=test mix db.reset
This task assumes you have postgres installed and that your current user can create / drop databases. If you'd prefer to use a different user, you can specify it with the environment variable SCRIVENER_ECTO_DB_USER
.
With the database built, you can now run the tests.
mix test